Chromable dyestuffs of the triarylmethane series and a process of preparing them



Patented May 20, 1941 CHROMABLE DYESTUFFS OF THE TRIARYL- IVIETHANESERIES AND A PROCESS OF PREPARING THEM Wilhelm =Eckert and KarlSchilling, Frankfort-ontlie- Main, Germany, assignors to General Aniline& Film Corporation, New York, N. Y., a corporation of Delaware NoDrawing. Application June 13, 1940, Serial I No. 340,324.

9 Claims.

The present invention relates to chromable dyestuffs of thetriarylmethane. series and to a processv of preparing them.

We have found that new dyestufis of. valuable fastness properties areobtainable by condensing one molecular proportion of 5sulfobenzene-1.2.4-tricar boxylic acidv or oftheisomeric3-sulfobenzene-1.2.4-tricarboxylic acid (5- or -3Sulfotrimellitic acid) of the formulae:

. coon c0011 o 0 on oo on;

and

H038 SQsH OOH soon or the equivalent amount of the anhydrides or thealkali metal salts of these acids, withtwo molecular proportions of anaromatic hydroxy compound having areactive nuclear hydrogen atom andcontaining, in meta-position to the hydroxy group, a substitutedaminogroup or another hydroxy group.

Suitable aromatic-hydroxy compounds having a reactiye nuclear'hydrogenatom and, metaposition to the hydroxy group, a substituted amino groupor another hydroxy group are, for instance:

Monoand di-N-substituted meta-aminophenols, such as3-methylamino-l-hydroxybenzene, 3-methylamino-1-hydroxy-4-methylbenzeneand the corresponding ethyl-, propyl-, butyl-, isobutyland higheralkyl-amino compounds; 3- dimethylamino 1 hydroxybenzene, 3dimethylamino-l-hydroxy-l-methylbenzene and the corresponding diethyl-,dipropyl-, dibutyl-, diisobutyland higher dialkyl-amino compounds; Nsubstituted meta aminophenols containing different substituents at thenitrogen atom, such In Germany June 21, 1939 as 3 methyl-ethylamino- 1hydroxybenzene 3- methyl-ethylaminol-hydroxyimethylbenzene, etc.N-substituted metaaminophenol compounds in which the substituentv at thenitrogen atom is an aromatic or heterocyclic radical, such as 3phenylamino 1 -hydroxybenzene, 3- (2.3' dimethylphenyl) amino 1hydroxybenzene and other substitutionproducts thereof; 3-piperidyl-1--hydroxybenzene (obtainable from resorcinol and piperidine at 150 C1),N'-(3-hydroxypheny1) morpholine (obtainable from resorcinol andmorpholine); N'-substituted meta-aminophenol compounds containingsuldalkylaminoand hydroxyalkylamino groups, such as B-disulfethylamino 1hydroxybenzene, 3 ethyl sulfethylamino-l-hydroxy 4- methylb enzene, 3methylsul'f'ethylamino 1 hydroxybenzene, B-dihydroxyethylamino 1-hydroxybenzene aromatic hydroxy compounds containing another hydroxygroup in meta position, such as 1.3-dihydroxybenzene and substituted1.3'-dihydroxybenzenes, for instance, halogen-1*.3-dihydroxybenzenes andnitro 1.3 dihydroxybenzenes, 4-carboxy-L3-dihydroxybenzene,1.2;3-trihydroxybenzene, methyl-1.3-dihydroxybenzene,3-methoxy-1-hydroxybenzene, 1.3-dihydroxynaphthalene, etc.

The condensationv of the, components is preferably carriedout in thepresence of a flux, such as the reaction product of pyridine, zincchloride and hydrochloric acid, by melting, the reagents at. atemperature of between about 150 C. and about 250 C.

The dyestuffs according to this invention which are obtained from5-sulfobenzene-1.2.4-tricarboxyclic. acid, have the following generalformula wherein the X's stand for a substituted amino group or for ahydroxy group and wherein the nuclei R may contain further substituents,

or they correspond to the isomeric compound COO HOOC

SOaH

wherein the Xs and Rs have the above meaning, as it is not certain whichof the two vicinal carboxyl groups forms the central carbon atom in thetriarylmethane dyestufis. Or the dyestufi's are mixtures of these twoisomeric compounds.

The dyestuffs which derive from 3-sulfobenzene-1.2.4-tricarboxylic acid,correspond to the formulae:

wherein the Xs and R's have the above mean' tricarboxylic acid(5-sulfo-trimellitic acid) obtainable by oxidation of the sodium salt ofthe 1.2A-trimethylbenzene-5-sulfonic acid with potassium permanganateand acidification of the filtered oxidation liquor with mineral acidsuntil the solution shows a feebly acid reaction'to Congo paper, and 150parts of 3-diethylamino-1- hydroxybenzene is introduced, while stirring,at 180 C. into 300 parts of a flux prepared from 1 mol each of pyridine,zinc chloride and hydrochloric acid. The temperature of the melt is thenraised to 200 C.-210 C. and maintained for about 4 hours, whilecontinuously stirring.

In order to isolate; the dyestufi, the rather thinly liquid red meltshowing a metallic surface lustre is poured on plates, the solidified,still warm cake is filled into a ball mill and ground therein until itis as fine as dust. The dyestuii powder thus obtained is introduced,while stirring, into 1000 parts of hydrochloric acid of 20 per cent.strength the powder dissolvingjthereby entirely. If this solution isslowly stirred into 5000 parts of a sodium chloride solution of percent. strength, the dyestuff separates in the form of a. red powderwhich is filtered with suction, washed with dilute sodium chloridesolution until it is neutral to Congo paper, and dried.

The dyestuflf thus obtained probably has the following constitution:

0 (ammo: UNKJflHBh C.

Naoas u coon or -the constitutionof the isomeric compound:

7 i acts: N(C2H5)2 ooo' S OaNa or the dyestuff constitutes a mixture ofthese isomeric compounds. It dyes animal fiber brilliant bluish-redtints; the fastness properties of these dyeings are considerablyimproved by afterchroming. (2)" By using parts ofB-diniethylamino-lhydroxybenzene instead of parts of3-dlethylamino-l-hydroxybenzene named in Example 1 and by carrying outthe process as described in said example, a dyestufi of similarproperties is obtained.

(3) An intimate mixture of 368 parts of the potassium salt of5-s'ulfobenzene-1.2.4-trlcarboxylic acid and 500 parts of the disodiumsalt of 3-disulfethylamino-l-hydroxybenzene of 72 per cent strength (therest being sodium chloride) is introduced, while stirring, at C. into800 parts of the flux named in Example 1. The temperature of the melt israised to 200 C. -220 A C. and maintained for 4-5 hours, whilecontinuously stirring the melt. The melt is allowed to cool and thenground, while excluding moisture, to a fine powder which is stirred into5000 parts of alcohol. The suspension produced of the dyestuff is boiledin a reflux condenser for 1 hour, while-stirring, and filtered withsuction while still hot. After the residue on the suction filter hasbeen washed for several times with alcohol and dried, a dyestufi remainsin the form of a redpowderwhich dyes animal fiber clear bluishred tints;the fastness properties of these dyelngs are considerably improved byafter-chromlng. The dyestuff probably has-the following constitution: 1'1 V I Naois nlo-nlo I CHz-CH SOsNa or the; constitution of. the.isomeric. compound. 20 per cent strength. After'coolingi there= isfil- Itered: with suction, washed with. a: solution of Naoss-Hic-Hio-/QH2-CHz-SQa-N&i sodium chloride and dried.

The dyestufi. has the formula:

HOOC/ to Na 3 or the dyestufi is amixture of these isomeric V Naois/compounds: CIQOH (4) 368 parts of the potassium salt of5-sulfobenzene-1.2.4-tricarboxylic: acid and 220 parts of 01 that thelsomenc compoundl.3-dihydroxybenzene are introduced, while stirring,at-,18.0' G. into 600pa-rts otthe-fiuxnamed 1'31. B'r- H in Example: 1.The temperature is; raised. to 200- O\ o /OH Cr and themixture is: kept.for 6 hours: at that 1 temperature; The dyestuif produced is isolated BrBr by extracting the cold; and; finely ground. melt with; 2000 parts: ofhot. water; the residue is ooo' washed with water untilz the zinc;chloride is removed and then dried.

The -dyestuii dies animal fiber brilliant yellow H000 tints; thefastness properties of thesedyeings' are considerably improved by;after-chroming. SOiN The d estuff robabl has; the. followin 'cona rStitutiong p y g or the dyestuif is a. mixture: of these isomericcompounds. It. dyes wool and. silkvery clear /O OH. yellowishered tints.After chromingv the. fastness; propenties of? the dyeings areparticularly remarkable. p

Q/ We claim: L. The compounds of the general formula ooo" 40 noas coon

or the constitution of the isomeric compound:

I wherein the X's represent radicals of the group 000 consisting ofhydroxy groups and substituted amino groups, one Y stands for thesulfonic acid group and the other Y for the carboxylic acid 1100c groupand wherein the nuclei B. may contain l further substituents.

2. The compound of the formula or the dyestufi is a mixture of theseisomeric I und 4 I aCmN O N(CaHs)2 (5) 24 parts of the dyestufi obtainedaccording to the process described in Example 4 are dissolved with 10parts of sodium carbonate and o/ 250 parts of water, while gentlyheating it, so 000' that a neutral yellow-red solution of the dyestufiis obtained. The solution is cooled to room temperature and, whilerapidly stirring, 32 parts of bromine are introduced, drop by drop, inthe Y proportion as it is consumed. A red precipitate Y graduallyseparates which, after the addition of the bromine is complete, isdissolved with 100 wherein one Y stands for the sulfonic acid groupparts of Zn-caustic soda solution; the solution and the other Y for thecarboxylic acid group, does not show an alkaline reaction. The solubeinga water-soluble dyestuff which dyes the tion is mixed with 50 parts ofsodium chloride, animal fiber vivid bluish-red tints, the fastness themixture is heated to about C. and the properties of the dyeings beingessentially endyestufi is precipitated with hydrochloric acid of 7hanced by after-chroming.

3.The compound of the general formula wherein one Y stands for thesulfonic acid group and the other Y for the carboxylic acid group, beinga water soluble dyestufi which dyes the animal fiber clear bluish-redtints, the fastness properties of the dyeings being essentially enhancedby after-chroming.

4. The compound of the formula HO- OH wherein one Y stands for thesulfonic acid group and the other Y for the carboxylic acid group,

'being a water soluble dyestufi which dyes the animal fiber vividyellow'tints, the fastness properties of the dyeings being essentiallyenhanced by after-chroming. g

The process whichcomprises causing one mol of asulfobenzene-1.2.4-tricarboxy1icacid of the formula:

coon 5 a oon wherein one X represents the sulfonic acid group and theother X hydrogen, to react with two mols of an aromatic hydroxy compoundhaving a reactive nuclear hydrogen atom and containing, in meta-positionto the hydroxy group, a substituent of the group consisting of asubstituted amino group and the hydroxy group by melting the reagents ata temperature of between about 150 0. and about 250 C.

6. The process which comprisescausing one mol of asulfobenzene-1.2.4-tricarboxy1ic acid of the formula:

COOH

, l 00H wherein one X represents thesulfonic acid group and the other' Xhydrogen, to react with two mols of an N-substi-tuted meta-amino-phenolcompound, containing a reactive'hydrogen atom in para-position to thesubstituted amino group, by melting the reagents at a temperature ofbetween about'150'C.:and about 250 C.

7. The process which comprises causing one mol of' the potassium salt of-5- sulfo-1.'2.4-tri-

